Figure 1: Two Enaliarctos Emlongi on the beach, which is part of their habitat. Source: http://piclib.nhm.ac.uk/piclib/www/comp.php?img=47082&frm=med
Habitat
The Extinct Enaliarctos Emlongi was a species of pinniped (fin-footed mammals), which evolved into the modern day Walrus, seals and sea lion. It lived about 13 to 20 million years ago in the late Oligocene period, overlapping with the early Miocene periods. This animal was extremely similar to the Puijila darwini, although it became extinct before the Enaliarctos Emlongi existed. It was discovered in the vicinity of what is now California and coastal Oregon, and named after fossil collector Douglas Emlong. The Enaliarctos Emlongi lived in the vicinity of where the modern California Sea Lion now lives.
Although information is limited, it is known that the animal lived in the coastal regions of the modern day US, where it has easy access to the open waters for hunting and to go back to shore to eat its food. The Enaliarctos Emlongi primarily ate fish and crustaceans (shelled animals such as ancient crab/lobster), hunting for food close to the coast at the bottom of the ocean floor. During the time period in which it existed, the temperature of the water in that area was much colder than modern day, although nowhere near as cold as the Arctic today, and they have thicker skins with fur for protection. They lived on the shore near the beaches, and go back and forth between the land and water to hunt and eat as well as rest.
Unlike the modern Walrus, which migrates according to the seasons to find the best hunting spot, the Enaliarctos Emlongi lived year long in the same environment. This is why the fossils of this animal are found exclusively in one area.
Figure 2: The Enaliarctos Emlongi swimming in the water of its habitat, most likely near the coastal regions. Source: http://upload.wikimedia.org/wikipedia/commons/6/67/Enaliarctos_emlongi.JPG
Behavioral Adaption
The Enaliarctos Emlongi is thought to have been required to return to shore once it has caught it’s prey, because it’s less advance and developed teeth means that it must be on land, where it is safer and easier, to start chewing and eating it’s food in order to ingest without problems. It helped the Ancestor Walrus because it meant that when it was at it’s most vulnerable time while eating where it is less able to sense predators, it would be on land where they have a better advantage in getting away. This is because they have not fully evolved into a marine creature yet, and still have a lot of characteristics of land animals which means that they will not be able to run away quickly enough in the water. By doing this they increase their chance of survival and those that don’t will often be eaten in the water easily by other predators of that time.
The Enaliarctos Emlongi swam with both its hind limbs and forelimbs, similar to the modern day Walrus Odobenus Rosamarus, although it is also the ancestors for the other related animals such as modern sea lions which only swims with their forelimbs or true seals which only use their hind limbs. This shows that the Ancestor Walrus had hind and forelimbs that were both very developed and used often, as opposed to some of the modern successors who have lost their reliance on some limbs for movement. The animal’s behaviour of using both to move shows that the Enaliarctos Emlongi is an amphibious animal that is equally suited to land and water. By doing this, they are more adaptive of the environment and can move freely between the land or water to hunt or avoid predators easier. The reason they adapted to move with both hind and fore limbs is because while they hunt in the water for food, they must eat it on land to ingest it properly.
Structural Adaption
The Ancestor walrus featured webbed feet, which helped it swim around in water, where it’s primary habitat and hunting grounds were. The webbed feet were useful for propulsion, especially used alongside the animal’s streamlined shape and short tail which is used in conjunction to move about quickly and nimbly underwater. By being agile, the Ancestor Walrus could more easily hunt prey and evade natural predators. The pressure that gave rise to this adaption was that those animals that could not swim quickly enough in the water would be unable to catch faster prey, or run away from predators, so they had to either adapt or be eaten, and the ones that were better at swimming due to their webbed feet survived to pass their genes.
The Ancestor of the Walrus Enaliarctos emlongi also had a very acute eyesight both in and out of the water, similar to the modern Bottlenose Dolphin and sensitive whiskers called vibrissae, similar to modern day Walruses, and are believed to have good eyesight as well as touch sensing like it’s successor. These two things allow them to see and feel better, especially when hunting underwater where they may need both to effectively seek out food and swim around. The reason that they developed these characteristics was because they needed them in order to effectively sense danger and be able to see and feel around their environment well. Those that couldn’t see the predators were killed.
Figure 3: The fossil remains of the Enaliarctos Emlongi, showing some of its structural features. Source: http://upload.wikimedia.org/wikipedia/commons/thumb/6/64/Enaliarctos_mealsi.JPG/200px-Enaliarctos_mealsi.JPG
Physiological Adaption
The Enaliarctos Emlongi has a special physiology in the ear which allows it to hear easily underwater. Through bone conduction in the skull, the animal can hear frequencies underwater that would normally be hard to pick up, due to sound travelling faster in the water than air. This adaption helps the animal as it can alert it of danger from predators far away, and communicate with other animals of the same species such as for mating practices. Because the animal spends so much time in the water, it is essential that it is aware of the environment when swimming because this will increase it’s chance of survival. Those that can’t hear underwater will often be eaten by predators because they won’t be able to hear them coming.
Figure 4: A diagram showing the Enaliarctos Emlongi's adaptation which helps them survive. Source: http://www.ysdw.net/UploadFile/2007-10/2007103861255381.jpg
Extinction Pressure
Ultimately, the animal became extinct as it could not adapt with the environment and survive. There were many predators in the area that the Enaliarctos Emlongi lived in, such as the Macrodelphinus kelloggi, which was a orca-like massively sized apex predator with inch long teeth, or the Eurhinodelphis genus Well-nosed Dolphins that had a long and sharp swordfish-like tip to stab prey with. Both of these predators and more probably contributed to the extinction of the ancestor animal as it could not swim fast enough to escape from them, due to their advantage in water with a better streamlined body and flippers, as opposed to the Enaliarctos Emlongi’s body, which has not fully developed enough to be as quick and agile underwater. They were all hunted down and killed by these marine predators, or other land predators.
Figure 5: Two of the Enaliarctos Emlongi's predators, the Macrodelphinus kelloggi and Eurhinodelphis Ambiguus Source: http://upload.wikimedia.org/wikipedia/commons/thumb/8/8c/Macrodelphinus_kelloggi.jpg/91px-Macrodelphinus_kelloggi.jpg
Future Animal Page: Odobenus Teres
Habitat
The Extinct Enaliarctos Emlongi was a species of pinniped (fin-footed mammals), which evolved into the modern day Walrus, seals and sea lion. It lived about 13 to 20 million years ago in the late Oligocene period, overlapping with the early Miocene periods. This animal was extremely similar to the Puijila darwini, although it became extinct before the Enaliarctos Emlongi existed. It was discovered in the vicinity of what is now California and coastal Oregon, and named after fossil collector Douglas Emlong. The Enaliarctos Emlongi lived in the vicinity of where the modern California Sea Lion now lives.
Although information is limited, it is known that the animal lived in the coastal regions of the modern day US, where it has easy access to the open waters for hunting and to go back to shore to eat its food. The Enaliarctos Emlongi primarily ate fish and crustaceans (shelled animals such as ancient crab/lobster), hunting for food close to the coast at the bottom of the ocean floor. During the time period in which it existed, the temperature of the water in that area was much colder than modern day, although nowhere near as cold as the Arctic today, and they have thicker skins with fur for protection. They lived on the shore near the beaches, and go back and forth between the land and water to hunt and eat as well as rest.
Unlike the modern Walrus, which migrates according to the seasons to find the best hunting spot, the Enaliarctos Emlongi lived year long in the same environment. This is why the fossils of this animal are found exclusively in one area.
Behavioral Adaption
The Enaliarctos Emlongi is thought to have been required to return to shore once it has caught it’s prey, because it’s less advance and developed teeth means that it must be on land, where it is safer and easier, to start chewing and eating it’s food in order to ingest without problems. It helped the Ancestor Walrus because it meant that when it was at it’s most vulnerable time while eating where it is less able to sense predators, it would be on land where they have a better advantage in getting away. This is because they have not fully evolved into a marine creature yet, and still have a lot of characteristics of land animals which means that they will not be able to run away quickly enough in the water. By doing this they increase their chance of survival and those that don’t will often be eaten in the water easily by other predators of that time.
The Enaliarctos Emlongi swam with both its hind limbs and forelimbs, similar to the modern day Walrus Odobenus Rosamarus, although it is also the ancestors for the other related animals such as modern sea lions which only swims with their forelimbs or true seals which only use their hind limbs. This shows that the Ancestor Walrus had hind and forelimbs that were both very developed and used often, as opposed to some of the modern successors who have lost their reliance on some limbs for movement. The animal’s behaviour of using both to move shows that the Enaliarctos Emlongi is an amphibious animal that is equally suited to land and water. By doing this, they are more adaptive of the environment and can move freely between the land or water to hunt or avoid predators easier. The reason they adapted to move with both hind and fore limbs is because while they hunt in the water for food, they must eat it on land to ingest it properly.
Structural Adaption
The Ancestor walrus featured webbed feet, which helped it swim around in water, where it’s primary habitat and hunting grounds were. The webbed feet were useful for propulsion, especially used alongside the animal’s streamlined shape and short tail which is used in conjunction to move about quickly and nimbly underwater. By being agile, the Ancestor Walrus could more easily hunt prey and evade natural predators. The pressure that gave rise to this adaption was that those animals that could not swim quickly enough in the water would be unable to catch faster prey, or run away from predators, so they had to either adapt or be eaten, and the ones that were better at swimming due to their webbed feet survived to pass their genes.
The Ancestor of the Walrus Enaliarctos emlongi also had a very acute eyesight both in and out of the water, similar to the modern Bottlenose Dolphin and sensitive whiskers called vibrissae, similar to modern day Walruses, and are believed to have good eyesight as well as touch sensing like it’s successor. These two things allow them to see and feel better, especially when hunting underwater where they may need both to effectively seek out food and swim around. The reason that they developed these characteristics was because they needed them in order to effectively sense danger and be able to see and feel around their environment well. Those that couldn’t see the predators were killed.
Physiological Adaption
The Enaliarctos Emlongi has a special physiology in the ear which allows it to hear easily underwater. Through bone conduction in the skull, the animal can hear frequencies underwater that would normally be hard to pick up, due to sound travelling faster in the water than air. This adaption helps the animal as it can alert it of danger from predators far away, and communicate with other animals of the same species such as for mating practices. Because the animal spends so much time in the water, it is essential that it is aware of the environment when swimming because this will increase it’s chance of survival. Those that can’t hear underwater will often be eaten by predators because they won’t be able to hear them coming.
Extinction Pressure
Ultimately, the animal became extinct as it could not adapt with the environment and survive. There were many predators in the area that the Enaliarctos Emlongi lived in, such as the Macrodelphinus kelloggi, which was a orca-like massively sized apex predator with inch long teeth, or the Eurhinodelphis genus Well-nosed Dolphins that had a long and sharp swordfish-like tip to stab prey with. Both of these predators and more probably contributed to the extinction of the ancestor animal as it could not swim fast enough to escape from them, due to their advantage in water with a better streamlined body and flippers, as opposed to the Enaliarctos Emlongi’s body, which has not fully developed enough to be as quick and agile underwater. They were all hunted down and killed by these marine predators, or other land predators.
Reference
Wikipedia. (2010). Enaliarctos. Retrieved July 18, 2010, from http://en.wikipedia.org/wiki/Enaliarctos
Academic Dictionaries and Encyclopedias. (2010). Enaliarctos emlongi. Retrieved July 19, 2010, from http://en.academic.ru/dic.nsf/enwiki/7946000
World Lingo. (2010). Enaliarctos. Retrieved July 20, 2010, from http://www.worldlingo.com/ma/enwiki/en/Enaliarctos
The Paleobiology Database. (2010). Enaliarctos emlongi. Retrieved July 21, 2010, from http://museumu03.museumwww.naturkundemuseum-berlin.de/cgi-bin/bridge.pl?action=checkTaxonInfo&taxon_no=71880